pi bond

A pi bond is a type of bond that is related to the p orbitals of an atom. A normal (sigma bond) bond is a direct interaction between the orbitals of two atoms. However, how can an atoms have more than one bond, such as carbon which can create a triple bond, when the other p orbitals are pointing away? The answer is the pi bond, which is a bond between two parallel p orbitals in each bond.

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Best pictured as the blank space between the vertical lines being the atoms, the horizontal lines are the bond. While it looks like there's two bonds, the pi bond has bands of dense electron probability, but is really considered one bond. The second pi bond can come from the p orbital that is perpendicular to the original pi bond, but on the same place, rather than the plane of the sigma bond.